The present invention relates to electric hair clippers, trimmers and shavers, and specifically to such devices having blade assemblies which are pivotable and/or rotatable, and in some cases detachable relative to the handle.
Presently there are two tools used to clip patients' hair prior to surgery: the disposable manual razor, and the electric clipper. Aside from its total disposability, which is a sanitary advantage, a major advantage of the manual razor is that it provides a stubble-free surface preferred by many physicians. However, clinical studies have shown that nicks caused by pre-operative shaving with razors may contribute to post-operative infections. Thus, many physicians are now recommending that such shaving be done with electric clippers, which clear the operation site of the majority of unwanted hair to improve visibility without causing infections.
Conventionally available electric clippers include two main components: a combined handle and drive system, and a removable, disposable blade assembly. The blade assembly includes a housing enclosing a fixed blade and a moving blade coaxially reciprocating relative to the fixed blade. When used in medical applications, the blade assembly is packaged in a sealed bag for sterility. Just prior to surgery, the hospital technician opens the bag and attaches the blade assembly to the handle. Upon completion of the shaving operation, the blade assembly is removed and discarded.
One disadvantage of these conventional clipper units with removable blade assemblies is the difficulty in properly engaging the blade assembly on the handle so that the drive member, normally a rotating eccentric cam member or reciprocating drive finger, will properly engage the cam follower in the reciprocating blade of the blade assembly. Conventional units require the operator or technician to perform relatively complicated multiple alignment and engagement steps to properly mount the blade assembly, which can be a frustrating and time consuming procedure.
Another disadvantage of conventional electric clippers used in surgery preparation is that once engaged upon the handle, the blade assembly is in a fixed position relative to the handle. Consequently, it is often awkward to properly shave certain hard-to-reach or sensitive body surfaces.
Yet another disadvantage of conventional clippers is that in some models the end of the blade assembly housing which slides along the skin is of insufficient surface area to enable the technician or operator to positively control the blade position or cutting angle as the clipper is passed over the skin or against a hair comb.
Still another disadvantage of conventional surgical clippers is that the removal of the blade assembly for disposal may subject the technician to contact with the sharp blades, with the resulting possibility of the technician becoming infected with diseases of the patient.
Thus, a first object of the present invention is to provide an improved hair clipper wherein the blade assembly is easily rotatable and pivotable in many directions.
Another object of the present invention is to provide an improved blade assembly for a hair clipper which is easily engaged upon the handle portion in a single movement without complicated manipulation, and which is also easy to remove without causing the operator or technician to contact the blades.
Yet another object of the present invention is to provide an improved blade assembly for a clipper wherein the blade housing provides sufficient surface area for facilitating operator control over the angle at which the blades cross the skin for the most efficient cutting over skin or against a hair comb.
Still another object of the present invention is to provide an improved disposable blade assembly for a clipper wherein the number of components is minimized to lower manufacturing and user costs.